UNIT STORYLINE How students will engage with each of the phenomena

HANDS-ON/ VIDEOS COMPUTER DATA SETS READINGS How can we make something new that was not there before? LAB ACTIVITIES OR IMAGES INTERACTIVES

Lesson Question Phenomena or Design Problem What we do and figure out How we represent it LESSON 1 We observe different bath bombs and what they do when added to water and then develop individual 4 days models and explanations to show what is happening at a scale smaller than we can see. We develop an What happens when a bath initial class consensus model, brainstorm related bomb is added to water (and phenomena, develop a DQB and ideas for what causes it to happen)? investigations to pursue. We figure out that: We had competing ideas for whether the matter Anchoring Phenomenon in the solid that we started with is still there after it is added to water. Some thought that it was all still there, while others thought not all of it was still there. We had competing ideas for where the gas came from that was in the bubbles that appeared. One was that it was there to start with (trapped inside When solid bath bombs are added to water, the solid). The other was that it formed from they start breaking apart, and gas bubbles some of the stuff we started with (e.g., in the appear on and around them for a few solid and/or water). minutes, until no solid is left.

⇓ Navigation to Next Lesson: We want to collect some data to see whether we can find evidence for the gas being in the solid before it is added to water.

LESSON 2 We investigate bath bombs, measuring their mass in a closed and open system before and after crushing 2 days them and before and after we add the bath bomb to water. We argue from evidence about where the gas Where is the gas coming came from. We figure out that: from? The gas we observed from the bath bomb does not come from any gas that was Investigation originally trapped in the bath bomb itself. Instead, the gas we observed when the bath bomb was placed in water comes from some change to the matter that is already there. The mass of a bath bomb put in water in an airtight container does not change, but the mass decreases after the cap on the bottle is opened and gas is heard escaping.

⇓ Navigation to Next Lesson: Students agree to investigate common ingredients in bath bombs next and to test each ingredient one at a time in water. Lesson Question Phenomena or Design Problem What we do and figure out How we represent it

LESSON 3 In this lesson, we make observations and collect data on each of the main ingredients in a bath bomb, 2 days recording the properties of each. We also investigate each ingredient as it mixes with water and record our What’s in a bath bomb that is observations. However, we see that the ingredients producing the gas? interact with water in different ways. We figure out that: Investigation Substances in the bath bomb have properties that can help us identify them (e.g., solubility, odor, state of matter at room temperature, melting point, density, and color). Mixing only one substance from a bath bomb with water does not cause gas bubbles to Bath bombs have different ingredients and appear. recipes. The ingredients in them interact with water in different ways, but none cause bubbles to appear when added to water on their own.

⇓ Navigation to Next Lesson: We figured out that a bath bomb has several ingredients, and these are called substances. These substances all have different properties. We figured out that mixing one substance with water does not make gas bubbles. We wonder if mixing two substances in water will produce gas bubbles, and if so, can we figure out which substances produce gas bubbles?

LESSON 4 We will discuss and record what we’ve figured out so far in the unit. We will plan and carry out an 2 days investigation to test different combinations of substances from a bath bomb, and we will use the Which combinations of the results to argue that the gas produced must be a new substances in a bath bomb substance. We figure out that: produce a gas? Citric acid and baking soda combined are the only substances from the bath bomb that, Putting Pieces Together, Investigation when combined with water, cause gas bubbles to form. The gas(es) in the bubbles are substance(s) that are different from any of the substances we started with.

Combining citric acid, baking soda, and water causes bubbles to appear. Lemonade mixes (which are made of specific substances, including citric acid) also caused bubbles when combined with water and baking soda.

⇓ Navigation to Next Lesson: Since we know that the gas in those bubbles is a different substance(s) that wasn’t there to start with, we want to try and figure out what substance(s) the gas is. We want to try to capture that gas and test it to figure that out. Lesson Question Phenomena or Design Problem What we do and figure out How we represent it

LESSON 5 We brainstorm phenomena related to gases and identify some different properties. We analyze the 2 days data by taking into account common gases and their known densities and flammabilities. We test the What gas(es) could be coming flammability of air from the room, gas from the bath from the bath bomb? bomb, and helium gas. We carry out an investigation to see if gas from the bath bomb rises or sinks. We Investigation argue from evidence (density and flammability data) that the gas from the bath bomb can be narrowed down to three candidate substances. We figure out that: Density and flammability are properties. In high concentrations, gases that are non- flammable will extinguish a flame. Materials that are less dense float upward when surrounded by matter that is more dense; materials that are more dense sink downward when surrounded by matter that is less dense. The gas from the bath bomb could be A flame goes out when put into a container of nitrogen, argon, or carbon dioxide. pure helium gas, gas from a bath bomb, or air mixed with helium, but does not when put in air only.

⇓ Navigation to Next Lesson: We want to see if we can explain a related phenomena using what we have figured out so far about property data. We want to see if we can explain a related phenomena using what we have figured out so far about property data.

LESSON 6 We apply what we have figured out about properties to explain a related phenomena (elephant’s 1 day toothpaste). We revisit our DQB and reflect on what other related phenomena we might explain using the How can we explain another same key model ideas. We figure out that: phenomenon where gas The mass of a partially open system where bubbles appear from potassium iodide and hydrogen peroxide are combined decreases because a gas is formed combining different and some of it escapes the system. substances together? When different substances are combined The gas makes a glowing ember burst into Putting Pieces Together flame and an already burning flame glow (potassium chloride and hydrogen peroxide), brighter. they interact and produce a gas. Flammability data can help identify the types of gases that aren’t being produced. Testing the melting/freezing point, density, and/or comparing the results of the flammability test to results from controls could help identify additional gases that aren’t being produced in this process.

⇓ Navigation to Next Lesson: We know that the possible candidate substances that are in the gas from those bubbles are a different substance(s) that wasn’t there to start with. Therefore, we wanted to try to develop a model at a particle level to explain how it is possible that a new substance that wasn’t there before was produced from different substances we started with. Lesson Question Phenomena or Design Problem What we do and figure out How we represent it

LESSON 7 We work as a class to summarize and review all of the science ideas we have figured out through the 1 day investigations we have done so far in order to put all the pieces together. We develop a new way to How can we revise our model represent what we figured out, using an input/output to represent the differences in table. We identify an unanswered question about the matter that goes into and where the particles that make up the substance(s) of the gas came from and individually develop a model comes out of the bath bomb to try to explain this.We figure out that: system? The same substance is made of the same type Putting Pieces Together of particles throughout. Different substances are made of different materials throughout. No new phenomena are introduced in this The particles that make up the substances in lesson. We put the pieces together for all the gas bubbles from a bath bomb must be a phenomena previously explored in Lessons 1 different type of particle than any of those in through 5. the substances that were combined together to make it (water, baking soda, and citric acid).

⇓ Navigation to Next Lesson: Since the only way there can be a new substance formed is if new particles were formed, we want to see if it is really possible to make new types of particles (and therefore new substances) out of something that we think is made of only one kind of particle.

LESSON 8 We develop alternate models for how new particles might be made from old particles using 1 day manipulatives (printed colored circles). We formulate questions we have about how we could figure out How can particles of a new what happens when new substances are made from substance be formed out of old. We read about what Dalton and other scientists the particles of an old did to see if adding energy to water could form new particles. We figure out that: substance? When new substances form from old Problematizing substances, the particles of the old substances might break apart and/or stick together to form new combinations of particles. We have a new line of investigations to pursue to see if new substances are formed when energy is added to a single substance (water).

Alternate models can help explain how to make new particles from old particles

⇓ Navigation to Next Lesson: We came up with some initial predictions about what substances are in the gas bubbles that form when you add energy to water. We have ideas of some property tests we can try to see if our predictions are right and we want to do some of those next. Lesson Question Phenomena or Design Problem What we do and figure out How we represent it

LESSON 9 We carry out an investigation to test the flammability of the gas produced by heating water. We collect data 2 days on the mass and volume of different samples of the water we started with and two other clear liquids and Does heating liquid water compare the mass and volume of each to the produce a new substance in substance we collected from the gas produced by the gas bubbles that appear? heating the water. We analyze graphs of the data and determine that the ratio of mass to volume for a Investigation substance is constant and that this is a property (density). We argue that the property data indicates that the gas we collected is made of the same particles that were in the water we started with. We figure out that: Density is calculated as a ratio of mass to volume (a unit rate). It is constant (a property) for any sample of a substance, regardless of size. The gas produced by the heated water is made of the same type of particles as those in the water that we started with. Gas from heated water extinguishes a flame. Clear liquid collected when gas cools has a mass to volume ratio of 1 for any size sample.

⇓ Navigation to Next Lesson: Now that we know that adding energy to water by heating it to make a gas doesn’t produce any new substances, and therefore no new types of particles, we want to see if adding energy to water using electricity might create new substances.

LESSON 10 We will carry out an investigation to test the flammability of gases produced by providing energy 1 day to water with electricity. We will construct an explanation for whether the gas(es) produced from When energy from a battery water using energy from a battery were made of the was added to water, were the same particles as those produced from heating the gases produced made of the water. We figure out that: Two different gases with different properties same particles as were are produced from adding energy from a produced from heating the battery to water. water? The particles that make up these different gases must be different from each other; they Investigation must also be different than the ones that were produced from heating water. The matter that makes up all of the substances must come from matter that When energy from a battery is added to made up some of the original water particles. water, two streams of gas bubbles are produced. When a lit match is put into trapped gas from these two sources, one pops and the other glows brighter.

⇓ Navigation to Next Lesson: We want to return to our poster “What is happening with particles when new substances are made?” and evaluate those ideas in light of the explanations we developed. Lesson Question Phenomena or Design Problem What we do and figure out How we represent it

LESSON 11 We gather and summarize information from a reading on investigations that Dalton and other 2 days scientists did and molecular models they developed for atoms, compound particles, chemical reactions, How do Dalton’s models of and substances. We will individually use those the particles that change in a models to predict and explain what gas is produced in reaction compare to the ones the bath bomb reaction and what is happening to the particles in the system. We figure out that: we developed? Molecules are made of atoms and all the substances in our world are made of very Investigation There are many different ways (symbols, shapes, letters, numbers, and physical few types of atoms. manipulatives) to represent the number, type, A substance is made of the same type of and arrangement of the atoms that make up molecules (or atoms throughout). The number, type, and arrangement of atoms in the molecules of different substances. the molecules that make up a substance are unique to that substance. In a chemical reaction, the particles that make up old substances can be broken apart and the atoms that make them up can be rearranged to form new molecules to make new substances.

⇓ Navigation to Next Lesson: We are ready to take stock of all that we have learned, revise our final model, and use it to explain the chemical reaction that takes place when a bath bomb is placed in water.

LESSON 12 We revise our consensus model with the molecules of the reactants and the gas produced from the bath 2 days bomb. We explain why it could be possible that water is also a product in this chemical reaction. Using How can a new substance (a property data and molecular models, we argue gas) be produced and the whether one the solids found in the container after total mass of the closed the water has been boiled off is a new substance. We develop a model to represent what is happening to system not change? particles in three different chemical processes. We Putting Pieces Together revisit the DQB and identify which questions we have made progress on. We figure out that: In a chemical reaction, the amount of matter at the beginning (in the reactants) is the same amount of matter at the end of the reaction (in the products). This is The mass of water captured in a container because all of the atoms we started with are after a bath bomb reacts in it is greater than still there. No new atoms can appear that was initially in the container before the bath weren’t there to start with. bomb was put in it. A white substance, with a Chemical reactions, phase changes, and different density and different solubility than dissolving are all chemical processes that any of the substances in the bath bomb is involve rearrangement of the particles that found in this container after the water is make up the matter in the system. boiled off.

⇓ Navigation to Next Lesson: We identified one line of questions that we made only a small bit of progress on related to odors. We have some ideas about how we might investigate this line of questions further. Lesson Question Phenomena or Design Problem What we do and figure out How we represent it

LESSON 13 We carry out an investigation about the scents of different substances to see if we can identify these 1 day substances by their odors. We gather information from a reading about how sensory receptors in our Why do different substances nose work. We use what we figure out from the odor have different odors and how lab and the reading to write an explanation about do we detect them? why different substances have different odors and how we detect them. We figure out that: Putting Pieces Together Odor is a property of a substance that is determined by the number, type, and arrangement of atoms that make up that substance. Molecules of substances must travel into our nose for us to detect an odor. Some substances can be identified by their Our nose has many different cells that each odor and each substance has a unique have different structures (sensory receptors molecular structure. These odors are received for odor) that different shaped molecules by the receptors in our nose and signals are can fit into, which will cause that cell to sent to our brain so we can recognize what the send a signal to other nerve cells that relay Patrick J. Lynch, medical illustrator; C. Carl substance is. that signal to our brain. Jaffe, MD, cardiologist. CCBY 2.5 Generic. The perception of different scents is the result of a combination of signals that the brain receives from different nerve cells.

⇓ Navigation to Next Lesson: We want to apply everything we figure out to another phenomenon in the world.

LESSON 14 We apply what we have figured out about properties to explain a related phenomena (pollution and 2 days erosion on marble). We carry out an investigation to collect data about what happens when different What is happening to the Taj substances in the air interact with marble. We identify Mahal? what other evidence we would want to collect in terms of property data to be able to argue whether a Putting Pieces Together chemical reaction occurs. We figure out: Two pollutants in the air around the Taj Mahal are interacting with the surface causing a chemical reaction to occur and change the surface to a new substance. Algae that is on the surface of the Taj Mahal The marble of the Taj Mahal is crumbling and secretes different acids that cause a falling apart. chemical reaction to occur with the (calcium carbonate) marble surface. The algae and pollutants in the air around the Taj Mahal are causing it to crumble due to chemical reactions that are occurring.

LESSONS 1-14 25 days total